Known air conditioning ducts for distributing air, which are made of a woven or non-woven fabric and which are also referred to as textile ducting outlets, typically consist of a material sewn together so as to form a closed shape having a specific cross section (ducting elements). The wall of a duct may be perforated or provided with through holes, the air distribution taking place through such perforation or holes. Distributing air in a proper manner is one of the most important functions of an air conditioning distribution system.
In certain cases, it is required that the direction of the distributed air flow is selectable between the downward one and the upward one, i.e. towards a ceiling, without necessitating the adjustment of the respective ducting element to be too complex. For this purpose, a ducting outlet combining two outlet types into one has been developed (FIG. 1). A membrane, which is made of a lightweight impervious fabric, is horizontally sewed into the centre of the ducting outlet. It alternately covers the first half or the second half of the ducting outlet. The front-end part of the membrane is attached to a shifting element actuated by a servomotor. Owing to this arrangement, two different positions may be selected, mostly a cooling position and a heating one. When assuming the heating position, the membrane overlaps the upper half of the ducting outlet, thus enabling air to exit through an array of holes in a downward direction. When assuming the cooling position, the membrane overlaps the lower half of the ducting outlet, thus enabling air to exit through a fabric or micro-perforation, the direction of the exiting air flow being limited to the upward one.
Furthermore, air-conditioning ducts having their longitudinal axes oriented in the vertical direction are known. In certain cases, the operation of such ducts is connected with requirements for getting the direction of the outlet air flow by means of a regulating membrane.
Moreover, known ducting elements are occasionally required to be temporarily fully closable. For example, various mechanisms made of metal materials and installed at the inlet end of the duct are used for this purpose. The material of such mechanisms causes a considerable increase in the overall weight on the one hand, and does not enable such closing mechanisms to be machine washed.
A shifting element according to the prior art substantially follows one half of the circumference of the cross section of the duct which means that it usually has a semi-circular shape. Thus, shifting of the element from one position to the other is carried out by turning the same by 180°. The drawbacks of the aforesaid technical solution consist in that the shifting action takes a relatively long time during which the membrane is subject to the highest strains (waving motion in an air flow) so that it becomes prone to be damaged. Moreover, a driving motor for turning the above mentioned element by 180° is relatively heavy, thus increasing the overall structural weight of the air-conditioning duct.